XXXI International Mineral Processing Congress 2024 Proceedings/Washington, DC/Sep 29–Oct 3 3069
the methodology employed in this study to indirectly infer
gold performance when necessary is valid.
Plant Trials
May 15, 2023, to June 12, 2023
On-stream results:
A total of 1075 data points were evaluated via the plant’s
online analyzer. During the period tested with Aerophine,
an average dosage of 89.5 g/t Aerophine, 17 g/t PAX,
and 0.3 g/t Dowfroth 250 was applied. Conversely, dur-
ing periods observed with PAX, a dosage of 83.5 g/t PAX,
23 g/t Hostaflot 7869, and 0.4 g/t Dowfroth 250 was
used. All plant data, including operational metrics like
energy consumption and production from primary and
secondary mills, ore grades analyzed by online XRF, and
chemicals used—totaling 19 variables—were statistically
analyzed using Bootstrap Forest combined with Boosted
Tree to assess predictors’ contribution to Au and Te recov-
ery responses. Results indicated that gold recovery is sig-
nificantly influenced by mill throughput and feed ore Au
grades, necessitating equivalent values for meaningful con-
clusions between evaluated collectors.
The particle size distribution for this period was ana-
lyzed and can be referenced in Figure 11. The particles are
fine, with a P80 of the feed close to 45 μm, 20 mm for the
rougher concentrate, and the P90 of the final concentrate
close to 20 mm.
Recovery results of Au and Te and mass pull as a func-
tion of Au grade obtained through the online XRF analyzer
of the plant are shown in Figure 12, where better perfor-
mance is observed with Aerophine. Table 3 summarizes the
mean values with statistical analysis at a 95% confidence
level for Aerophine and PAX, demonstrating equivalence
in plant productivity values. However, there is a higher feed
grade for Au and Te, necessitating a comparative analysis
with equivalent grades.
Therefore, data with lower feed grades with PAX were
removed, obtaining gold feed grades in the flotation plant
feed equivalent to 5.33 ppm for Aerophine and 5.32 ppm
for PAX with 95% statistical confidence, as shown in
Figure 13. This resulted in an observed increase in gold
grade in the concentrate from 319 ppm to 384 ppm and
from 1.1% to 1.8% for Te with Aerophine, as well as a
predicted recovery gain of 3 percentage points with the new
collector for gold, as presented in Figure 14, and 7 percent-
age points for tellurium. The reduction in mass pull con-
tinues to be relatively significant, with 35% less mass pull
using Aerophine due to better selectivity achieved.
Figure 11. Common particle size distribution for the plant feed “Feed,” rougher concentrate “R conc,”
and final concentrate “Conc”
the methodology employed in this study to indirectly infer
gold performance when necessary is valid.
Plant Trials
May 15, 2023, to June 12, 2023
On-stream results:
A total of 1075 data points were evaluated via the plant’s
online analyzer. During the period tested with Aerophine,
an average dosage of 89.5 g/t Aerophine, 17 g/t PAX,
and 0.3 g/t Dowfroth 250 was applied. Conversely, dur-
ing periods observed with PAX, a dosage of 83.5 g/t PAX,
23 g/t Hostaflot 7869, and 0.4 g/t Dowfroth 250 was
used. All plant data, including operational metrics like
energy consumption and production from primary and
secondary mills, ore grades analyzed by online XRF, and
chemicals used—totaling 19 variables—were statistically
analyzed using Bootstrap Forest combined with Boosted
Tree to assess predictors’ contribution to Au and Te recov-
ery responses. Results indicated that gold recovery is sig-
nificantly influenced by mill throughput and feed ore Au
grades, necessitating equivalent values for meaningful con-
clusions between evaluated collectors.
The particle size distribution for this period was ana-
lyzed and can be referenced in Figure 11. The particles are
fine, with a P80 of the feed close to 45 μm, 20 mm for the
rougher concentrate, and the P90 of the final concentrate
close to 20 mm.
Recovery results of Au and Te and mass pull as a func-
tion of Au grade obtained through the online XRF analyzer
of the plant are shown in Figure 12, where better perfor-
mance is observed with Aerophine. Table 3 summarizes the
mean values with statistical analysis at a 95% confidence
level for Aerophine and PAX, demonstrating equivalence
in plant productivity values. However, there is a higher feed
grade for Au and Te, necessitating a comparative analysis
with equivalent grades.
Therefore, data with lower feed grades with PAX were
removed, obtaining gold feed grades in the flotation plant
feed equivalent to 5.33 ppm for Aerophine and 5.32 ppm
for PAX with 95% statistical confidence, as shown in
Figure 13. This resulted in an observed increase in gold
grade in the concentrate from 319 ppm to 384 ppm and
from 1.1% to 1.8% for Te with Aerophine, as well as a
predicted recovery gain of 3 percentage points with the new
collector for gold, as presented in Figure 14, and 7 percent-
age points for tellurium. The reduction in mass pull con-
tinues to be relatively significant, with 35% less mass pull
using Aerophine due to better selectivity achieved.
Figure 11. Common particle size distribution for the plant feed “Feed,” rougher concentrate “R conc,”
and final concentrate “Conc”